diff options
Diffstat (limited to 'drivers/iommu/rockchip-iommu.c')
| -rw-r--r-- | drivers/iommu/rockchip-iommu.c | 1038 |
1 files changed, 1038 insertions, 0 deletions
diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c new file mode 100644 index 00000000000..b2023af384b --- /dev/null +++ b/drivers/iommu/rockchip-iommu.c @@ -0,0 +1,1038 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <asm/cacheflush.h> +#include <asm/pgtable.h> +#include <linux/compiler.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iommu.h> +#include <linux/jiffies.h> +#include <linux/list.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +/** MMU register offsets */ +#define RK_MMU_DTE_ADDR 0x00 /* Directory table address */ +#define RK_MMU_STATUS 0x04 +#define RK_MMU_COMMAND 0x08 +#define RK_MMU_PAGE_FAULT_ADDR 0x0C /* IOVA of last page fault */ +#define RK_MMU_ZAP_ONE_LINE 0x10 /* Shootdown one IOTLB entry */ +#define RK_MMU_INT_RAWSTAT 0x14 /* IRQ status ignoring mask */ +#define RK_MMU_INT_CLEAR 0x18 /* Acknowledge and re-arm irq */ +#define RK_MMU_INT_MASK 0x1C /* IRQ enable */ +#define RK_MMU_INT_STATUS 0x20 /* IRQ status after masking */ +#define RK_MMU_AUTO_GATING 0x24 + +#define DTE_ADDR_DUMMY 0xCAFEBABE +#define FORCE_RESET_TIMEOUT 100 /* ms */ + +/* RK_MMU_STATUS fields */ +#define RK_MMU_STATUS_PAGING_ENABLED BIT(0) +#define RK_MMU_STATUS_PAGE_FAULT_ACTIVE BIT(1) +#define RK_MMU_STATUS_STALL_ACTIVE BIT(2) +#define RK_MMU_STATUS_IDLE BIT(3) +#define RK_MMU_STATUS_REPLAY_BUFFER_EMPTY BIT(4) +#define RK_MMU_STATUS_PAGE_FAULT_IS_WRITE BIT(5) +#define RK_MMU_STATUS_STALL_NOT_ACTIVE BIT(31) + +/* RK_MMU_COMMAND command values */ +#define RK_MMU_CMD_ENABLE_PAGING 0 /* Enable memory translation */ +#define RK_MMU_CMD_DISABLE_PAGING 1 /* Disable memory translation */ +#define RK_MMU_CMD_ENABLE_STALL 2 /* Stall paging to allow other cmds */ +#define RK_MMU_CMD_DISABLE_STALL 3 /* Stop stall re-enables paging */ +#define RK_MMU_CMD_ZAP_CACHE 4 /* Shoot down entire IOTLB */ +#define RK_MMU_CMD_PAGE_FAULT_DONE 5 /* Clear page fault */ +#define RK_MMU_CMD_FORCE_RESET 6 /* Reset all registers */ + +/* RK_MMU_INT_* register fields */ +#define RK_MMU_IRQ_PAGE_FAULT 0x01 /* page fault */ +#define RK_MMU_IRQ_BUS_ERROR 0x02 /* bus read error */ +#define RK_MMU_IRQ_MASK (RK_MMU_IRQ_PAGE_FAULT | RK_MMU_IRQ_BUS_ERROR) + +#define NUM_DT_ENTRIES 1024 +#define NUM_PT_ENTRIES 1024 + +#define SPAGE_ORDER 12 +#define SPAGE_SIZE (1 << SPAGE_ORDER) + + /* + * Support mapping any size that fits in one page table: + * 4 KiB to 4 MiB + */ +#define RK_IOMMU_PGSIZE_BITMAP 0x007ff000 + +#define IOMMU_REG_POLL_COUNT_FAST 1000 + +struct rk_iommu_domain { + struct list_head iommus; + u32 *dt; /* page directory table */ + spinlock_t iommus_lock; /* lock for iommus list */ + spinlock_t dt_lock; /* lock for modifying page directory table */ +}; + +struct rk_iommu { + struct device *dev; + void __iomem *base; + int irq; + struct list_head node; /* entry in rk_iommu_domain.iommus */ + struct iommu_domain *domain; /* domain to which iommu is attached */ +}; + +static inline void rk_table_flush(u32 *va, unsigned int count) +{ + phys_addr_t pa_start = virt_to_phys(va); + phys_addr_t pa_end = virt_to_phys(va + count); + size_t size = pa_end - pa_start; + + __cpuc_flush_dcache_area(va, size); + outer_flush_range(pa_start, pa_end); +} + +/** + * Inspired by _wait_for in intel_drv.h + * This is NOT safe for use in interrupt context. + * + * Note that it's important that we check the condition again after having + * timed out, since the timeout could be due to preemption or similar and + * we've never had a chance to check the condition before the timeout. + */ +#define rk_wait_for(COND, MS) ({ \ + unsigned long timeout__ = jiffies + msecs_to_jiffies(MS) + 1; \ + int ret__ = 0; \ + while (!(COND)) { \ + if (time_after(jiffies, timeout__)) { \ + ret__ = (COND) ? 0 : -ETIMEDOUT; \ + break; \ + } \ + usleep_range(50, 100); \ + } \ + ret__; \ +}) + +/* + * The Rockchip rk3288 iommu uses a 2-level page table. + * The first level is the "Directory Table" (DT). + * The DT consists of 1024 4-byte Directory Table Entries (DTEs), each pointing + * to a "Page Table". + * The second level is the 1024 Page Tables (PT). + * Each PT consists of 1024 4-byte Page Table Entries (PTEs), each pointing to + * a 4 KB page of physical memory. + * + * The DT and each PT fits in a single 4 KB page (4-bytes * 1024 entries). + * Each iommu device has a MMU_DTE_ADDR register that contains the physical + * address of the start of the DT page. + * + * The structure of the page table is as follows: + * + * DT + * MMU_DTE_ADDR -> +-----+ + * | | + * +-----+ PT + * | DTE | -> +-----+ + * +-----+ | | Memory + * | | +-----+ Page + * | | | PTE | -> +-----+ + * +-----+ +-----+ | | + * | | | | + * | | | | + * +-----+ | | + * | | + * | | + * +-----+ + */ + +/* + * Each DTE has a PT address and a valid bit: + * +---------------------+-----------+-+ + * | PT address | Reserved |V| + * +---------------------+-----------+-+ + * 31:12 - PT address (PTs always starts on a 4 KB boundary) + * 11: 1 - Reserved + * 0 - 1 if PT @ PT address is valid + */ +#define RK_DTE_PT_ADDRESS_MASK 0xfffff000 +#define RK_DTE_PT_VALID BIT(0) + +static inline phys_addr_t rk_dte_pt_address(u32 dte) +{ + return (phys_addr_t)dte & RK_DTE_PT_ADDRESS_MASK; +} + +static inline bool rk_dte_is_pt_valid(u32 dte) +{ + return dte & RK_DTE_PT_VALID; +} + +static u32 rk_mk_dte(u32 *pt) +{ + phys_addr_t pt_phys = virt_to_phys(pt); + return (pt_phys & RK_DTE_PT_ADDRESS_MASK) | RK_DTE_PT_VALID; +} + +/* + * Each PTE has a Page address, some flags and a valid bit: + * +---------------------+---+-------+-+ + * | Page address |Rsv| Flags |V| + * +---------------------+---+-------+-+ + * 31:12 - Page address (Pages always start on a 4 KB boundary) + * 11: 9 - Reserved + * 8: 1 - Flags + * 8 - Read allocate - allocate cache space on read misses + * 7 - Read cache - enable cache & prefetch of data + * 6 - Write buffer - enable delaying writes on their way to memory + * 5 - Write allocate - allocate cache space on write misses + * 4 - Write cache - different writes can be merged together + * 3 - Override cache attributes + * if 1, bits 4-8 control cache attributes + * if 0, the system bus defaults are used + * 2 - Writable + * 1 - Readable + * 0 - 1 if Page @ Page address is valid + */ +#define RK_PTE_PAGE_ADDRESS_MASK 0xfffff000 +#define RK_PTE_PAGE_FLAGS_MASK 0x000001fe +#define RK_PTE_PAGE_WRITABLE BIT(2) +#define RK_PTE_PAGE_READABLE BIT(1) +#define RK_PTE_PAGE_VALID BIT(0) + +static inline phys_addr_t rk_pte_page_address(u32 pte) +{ + return (phys_addr_t)pte & RK_PTE_PAGE_ADDRESS_MASK; +} + +static inline bool rk_pte_is_page_valid(u32 pte) +{ + return pte & RK_PTE_PAGE_VALID; +} + +/* TODO: set cache flags per prot IOMMU_CACHE */ +static u32 rk_mk_pte(phys_addr_t page, int prot) +{ + u32 flags = 0; + flags |= (prot & IOMMU_READ) ? RK_PTE_PAGE_READABLE : 0; + flags |= (prot & IOMMU_WRITE) ? RK_PTE_PAGE_WRITABLE : 0; + page &= RK_PTE_PAGE_ADDRESS_MASK; + return page | flags | RK_PTE_PAGE_VALID; +} + +static u32 rk_mk_pte_invalid(u32 pte) +{ + return pte & ~RK_PTE_PAGE_VALID; +} + +/* + * rk3288 iova (IOMMU Virtual Address) format + * 31 22.21 12.11 0 + * +-----------+-----------+-------------+ + * | DTE index | PTE index | Page offset | + * +-----------+-----------+-------------+ + * 31:22 - DTE index - index of DTE in DT + * 21:12 - PTE index - index of PTE in PT @ DTE.pt_address + * 11: 0 - Page offset - offset into page @ PTE.page_address + */ +#define RK_IOVA_DTE_MASK 0xffc00000 +#define RK_IOVA_DTE_SHIFT 22 +#define RK_IOVA_PTE_MASK 0x003ff000 +#define RK_IOVA_PTE_SHIFT 12 +#define RK_IOVA_PAGE_MASK 0x00000fff +#define RK_IOVA_PAGE_SHIFT 0 + +static u32 rk_iova_dte_index(dma_addr_t iova) +{ + return (u32)(iova & RK_IOVA_DTE_MASK) >> RK_IOVA_DTE_SHIFT; +} + +static u32 rk_iova_pte_index(dma_addr_t iova) +{ + return (u32)(iova & RK_IOVA_PTE_MASK) >> RK_IOVA_PTE_SHIFT; +} + +static u32 rk_iova_page_offset(dma_addr_t iova) +{ + return (u32)(iova & RK_IOVA_PAGE_MASK) >> RK_IOVA_PAGE_SHIFT; +} + +static u32 rk_iommu_read(struct rk_iommu *iommu, u32 offset) +{ + return readl(iommu->base + offset); +} + +static void rk_iommu_write(struct rk_iommu *iommu, u32 offset, u32 value) +{ + writel(value, iommu->base + offset); +} + +static void rk_iommu_command(struct rk_iommu *iommu, u32 command) +{ + writel(command, iommu->base + RK_MMU_COMMAND); +} + +static void rk_iommu_zap_lines(struct rk_iommu *iommu, dma_addr_t iova, + size_t size) +{ + dma_addr_t iova_end = iova + size; + /* + * TODO(djkurtz): Figure out when it is more efficient to shootdown the + * entire iotlb rather than iterate over individual iovas. + */ + for (; iova < iova_end; iova += SPAGE_SIZE) + rk_iommu_write(iommu, RK_MMU_ZAP_ONE_LINE, iova); +} + +static bool rk_iommu_is_stall_active(struct rk_iommu *iommu) +{ + return rk_iommu_read(iommu, RK_MMU_STATUS) & RK_MMU_STATUS_STALL_ACTIVE; +} + +static bool rk_iommu_is_paging_enabled(struct rk_iommu *iommu) +{ + return rk_iommu_read(iommu, RK_MMU_STATUS) & + RK_MMU_STATUS_PAGING_ENABLED; +} + +static int rk_iommu_enable_stall(struct rk_iommu *iommu) +{ + int ret; + + if (rk_iommu_is_stall_active(iommu)) + return 0; + + /* Stall can only be enabled if paging is enabled */ + if (!rk_iommu_is_paging_enabled(iommu)) + return 0; + + rk_iommu_command(iommu, RK_MMU_CMD_ENABLE_STALL); + + ret = rk_wait_for(rk_iommu_is_stall_active(iommu), 1); + if (ret) + dev_err(iommu->dev, "Enable stall request timed out, status: %#08x\n", + rk_iommu_read(iommu, RK_MMU_STATUS)); + + return ret; +} + +static int rk_iommu_disable_stall(struct rk_iommu *iommu) +{ + int ret; + + if (!rk_iommu_is_stall_active(iommu)) + return 0; + + rk_iommu_command(iommu, RK_MMU_CMD_DISABLE_STALL); + + ret = rk_wait_for(!rk_iommu_is_stall_active(iommu), 1); + if (ret) + dev_err(iommu->dev, "Disable stall request timed out, status: %#08x\n", + rk_iommu_read(iommu, RK_MMU_STATUS)); + + return ret; +} + +static int rk_iommu_enable_paging(struct rk_iommu *iommu) +{ + int ret; + + if (rk_iommu_is_paging_enabled(iommu)) + return 0; + + rk_iommu_command(iommu, RK_MMU_CMD_ENABLE_PAGING); + + ret = rk_wait_for(rk_iommu_is_paging_enabled(iommu), 1); + if (ret) + dev_err(iommu->dev, "Enable paging request timed out, status: %#08x\n", + rk_iommu_read(iommu, RK_MMU_STATUS)); + + return ret; +} + +static int rk_iommu_disable_paging(struct rk_iommu *iommu) +{ + int ret; + + if (!rk_iommu_is_paging_enabled(iommu)) + return 0; + + rk_iommu_command(iommu, RK_MMU_CMD_DISABLE_PAGING); + + ret = rk_wait_for(!rk_iommu_is_paging_enabled(iommu), 1); + if (ret) + dev_err(iommu->dev, "Disable paging request timed out, status: %#08x\n", + rk_iommu_read(iommu, RK_MMU_STATUS)); + + return ret; +} + +static int rk_iommu_force_reset(struct rk_iommu *iommu) +{ + int ret; + u32 dte_addr; + + /* + * Check if register DTE_ADDR is working by writing DTE_ADDR_DUMMY + * and verifying that upper 5 nybbles are read back. + */ + rk_iommu_write(iommu, RK_MMU_DTE_ADDR, DTE_ADDR_DUMMY); + + dte_addr = rk_iommu_read(iommu, RK_MMU_DTE_ADDR); + if (dte_addr != (DTE_ADDR_DUMMY & RK_DTE_PT_ADDRESS_MASK)) { + dev_err(iommu->dev, "Error during raw reset. MMU_DTE_ADDR is not functioning\n"); + return -EFAULT; + } + + rk_iommu_command(iommu, RK_MMU_CMD_FORCE_RESET); + + ret = rk_wait_for(rk_iommu_read(iommu, RK_MMU_DTE_ADDR) == 0x00000000, + FORCE_RESET_TIMEOUT); + if (ret) + dev_err(iommu->dev, "FORCE_RESET command timed out\n"); + + return ret; +} + +static void log_iova(struct rk_iommu *iommu, dma_addr_t iova) +{ + u32 dte_index, pte_index, page_offset; + u32 mmu_dte_addr; + phys_addr_t mmu_dte_addr_phys, dte_addr_phys; + u32 *dte_addr; + u32 dte; + phys_addr_t pte_addr_phys = 0; + u32 *pte_addr = NULL; + u32 pte = 0; + phys_addr_t page_addr_phys = 0; + u32 page_flags = 0; + + dte_index = rk_iova_dte_index(iova); + pte_index = rk_iova_pte_index(iova); + page_offset = rk_iova_page_offset(iova); + + mmu_dte_addr = rk_iommu_read(iommu, RK_MMU_DTE_ADDR); + mmu_dte_addr_phys = (phys_addr_t)mmu_dte_addr; + + dte_addr_phys = mmu_dte_addr_phys + (4 * dte_index); + dte_addr = phys_to_virt(dte_addr_phys); + dte = *dte_addr; + + if (!rk_dte_is_pt_valid(dte)) + goto print_it; + + pte_addr_phys = rk_dte_pt_address(dte) + (pte_index * 4); + pte_addr = phys_to_virt(pte_addr_phys); + pte = *pte_addr; + + if (!rk_pte_is_page_valid(pte)) + goto print_it; + + page_addr_phys = rk_pte_page_address(pte) + page_offset; + page_flags = pte & RK_PTE_PAGE_FLAGS_MASK; + +print_it: + dev_err(iommu->dev, "iova = %pad: dte_index: %#03x pte_index: %#03x page_offset: %#03x\n", + &iova, dte_index, pte_index, page_offset); + dev_err(iommu->dev, "mmu_dte_addr: %pa dte@%pa: %#08x valid: %u pte@%pa: %#08x valid: %u page@%pa flags: %#03x\n", + &mmu_dte_addr_phys, &dte_addr_phys, dte, + rk_dte_is_pt_valid(dte), &pte_addr_phys, pte, + rk_pte_is_page_valid(pte), &page_addr_phys, page_flags); +} + +static irqreturn_t rk_iommu_irq(int irq, void *dev_id) +{ + struct rk_iommu *iommu = dev_id; + u32 status; + u32 int_status; + dma_addr_t iova; + + int_status = rk_iommu_read(iommu, RK_MMU_INT_STATUS); + if (int_status == 0) + return IRQ_NONE; + + iova = rk_iommu_read(iommu, RK_MMU_PAGE_FAULT_ADDR); + + if (int_status & RK_MMU_IRQ_PAGE_FAULT) { + int flags; + + status = rk_iommu_read(iommu, RK_MMU_STATUS); + flags = (status & RK_MMU_STATUS_PAGE_FAULT_IS_WRITE) ? + IOMMU_FAULT_WRITE : IOMMU_FAULT_READ; + + dev_err(iommu->dev, "Page fault at %pad of type %s\n", + &iova, + (flags == IOMMU_FAULT_WRITE) ? "write" : "read"); + + log_iova(iommu, iova); + + /* + * Report page fault to any installed handlers. + * Ignore the return code, though, since we always zap cache + * and clear the page fault anyway. + */ + if (iommu->domain) + report_iommu_fault(iommu->domain, iommu->dev, iova, + flags); + else + dev_err(iommu->dev, "Page fault while iommu not attached to domain?\n"); + + rk_iommu_command(iommu, RK_MMU_CMD_ZAP_CACHE); + rk_iommu_command(iommu, RK_MMU_CMD_PAGE_FAULT_DONE); + } + + if (int_status & RK_MMU_IRQ_BUS_ERROR) + dev_err(iommu->dev, "BUS_ERROR occurred at %pad\n", &iova); + + if (int_status & ~RK_MMU_IRQ_MASK) + dev_err(iommu->dev, "unexpected int_status: %#08x\n", + int_status); + + rk_iommu_write(iommu, RK_MMU_INT_CLEAR, int_status); + + return IRQ_HANDLED; +} + +static phys_addr_t rk_iommu_iova_to_phys(struct iommu_domain *domain, + dma_addr_t iova) +{ + struct rk_iommu_domain *rk_domain = domain->priv; + unsigned long flags; + phys_addr_t pt_phys, phys = 0; + u32 dte, pte; + u32 *page_table; + + spin_lock_irqsave(&rk_domain->dt_lock, flags); + + dte = rk_domain->dt[rk_iova_dte_index(iova)]; + if (!rk_dte_is_pt_valid(dte)) + goto out; + + pt_phys = rk_dte_pt_address(dte); + page_table = (u32 *)phys_to_virt(pt_phys); + pte = page_table[rk_iova_pte_index(iova)]; + if (!rk_pte_is_page_valid(pte)) + goto out; + + phys = rk_pte_page_address(pte) + rk_iova_page_offset(iova); +out: + spin_unlock_irqrestore(&rk_domain->dt_lock, flags); + + return phys; +} + +static void rk_iommu_zap_iova(struct rk_iommu_domain *rk_domain, + dma_addr_t iova, size_t size) +{ + struct list_head *pos; + unsigned long flags; + + /* shootdown these iova from all iommus using this domain */ + spin_lock_irqsave(&rk_domain->iommus_lock, flags); + list_for_each(pos, &rk_domain->iommus) { + struct rk_iommu *iommu; + iommu = list_entry(pos, struct rk_iommu, node); + rk_iommu_zap_lines(iommu, iova, size); + } + spin_unlock_irqrestore(&rk_domain->iommus_lock, flags); +} + +static u32 *rk_dte_get_page_table(struct rk_iommu_domain *rk_domain, + dma_addr_t iova) +{ + u32 *page_table, *dte_addr; + u32 dte; + phys_addr_t pt_phys; + + assert_spin_locked(&rk_domain->dt_lock); + + dte_addr = &rk_domain->dt[rk_iova_dte_index(iova)]; + dte = *dte_addr; + if (rk_dte_is_pt_valid(dte)) + goto done; + + page_table = (u32 *)get_zeroed_page(GFP_ATOMIC | GFP_DMA32); + if (!page_table) + return ERR_PTR(-ENOMEM); + + dte = rk_mk_dte(page_table); + *dte_addr = dte; + + rk_table_flush(page_table, NUM_PT_ENTRIES); + rk_table_flush(dte_addr, 1); + + /* + * Zap the first iova of newly allocated page table so iommu evicts + * old cached value of new dte from the iotlb. + */ + rk_iommu_zap_iova(rk_domain, iova, SPAGE_SIZE); + +done: + pt_phys = rk_dte_pt_address(dte); + return (u32 *)phys_to_virt(pt_phys); +} + +static size_t rk_iommu_unmap_iova(struct rk_iommu_domain *rk_domain, + u32 *pte_addr, dma_addr_t iova, size_t size) +{ + unsigned int pte_count; + unsigned int pte_total = size / SPAGE_SIZE; + + assert_spin_locked(&rk_domain->dt_lock); + + for (pte_count = 0; pte_count < pte_total; pte_count++) { + u32 pte = pte_addr[pte_count]; + if (!rk_pte_is_page_valid(pte)) + break; + + pte_addr[pte_count] = rk_mk_pte_invalid(pte); + } + + rk_table_flush(pte_addr, pte_count); + + return pte_count * SPAGE_SIZE; +} + +static int rk_iommu_map_iova(struct rk_iommu_domain *rk_domain, u32 *pte_addr, + dma_addr_t iova, phys_addr_t paddr, size_t size, + int prot) +{ + unsigned int pte_count; + unsigned int pte_total = size / SPAGE_SIZE; + phys_addr_t page_phys; + + assert_spin_locked(&rk_domain->dt_lock); + + for (pte_count = 0; pte_count < pte_total; pte_count++) { + u32 pte = pte_addr[pte_count]; + + if (rk_pte_is_page_valid(pte)) + goto unwind; + + pte_addr[pte_count] = rk_mk_pte(paddr, prot); + + paddr += SPAGE_SIZE; + } + + rk_table_flush(pte_addr, pte_count); + + return 0; +unwind: + /* Unmap the range of iovas that we just mapped */ + rk_iommu_unmap_iova(rk_domain, pte_addr, iova, pte_count * SPAGE_SIZE); + + iova += pte_count * SPAGE_SIZE; + page_phys = rk_pte_page_address(pte_addr[pte_count]); + pr_err("iova: %pad already mapped to %pa cannot remap to phys: %pa prot: %#x\n", + &iova, &page_phys, &paddr, prot); + + return -EADDRINUSE; +} + +static int rk_iommu_map(struct iommu_domain *domain, unsigned long _iova, + phys_addr_t paddr, size_t size, int prot) +{ + struct rk_iommu_domain *rk_domain = domain->priv; + unsigned long flags; + dma_addr_t iova = (dma_addr_t)_iova; + u32 *page_table, *pte_addr; + int ret; + + spin_lock_irqsave(&rk_domain->dt_lock, flags); + + /* + * pgsize_bitmap specifies iova sizes that fit in one page table + * (1024 4-KiB pages = 4 MiB). + * So, size will always be 4096 <= size <= 4194304. + * Since iommu_map() guarantees that both iova and size will be + * aligned, we will always only be mapping from a single dte here. + */ + page_table = rk_dte_get_page_table(rk_domain, iova); + if (IS_ERR(page_table)) { + spin_unlock_irqrestore(&rk_domain->dt_lock, flags); + return PTR_ERR(page_table); + } + + pte_addr = &page_table[rk_iova_pte_index(iova)]; + ret = rk_iommu_map_iova(rk_domain, pte_addr, iova, paddr, size, prot); + spin_unlock_irqrestore(&rk_domain->dt_lock, flags); + + return ret; +} + +static size_t rk_iommu_unmap(struct iommu_domain *domain, unsigned long _iova, + size_t size) +{ + struct rk_iommu_domain *rk_domain = domain->priv; + unsigned long flags; + dma_addr_t iova = (dma_addr_t)_iova; + phys_addr_t pt_phys; + u32 dte; + u32 *pte_addr; + size_t unmap_size; + + spin_lock_irqsave(&rk_domain->dt_lock, flags); + + /* + * pgsize_bitmap specifies iova sizes that fit in one page table + * (1024 4-KiB pages = 4 MiB). + * So, size will always be 4096 <= size <= 4194304. + * Since iommu_unmap() guarantees that both iova and size will be + * aligned, we will always only be unmapping from a single dte here. + */ + dte = rk_domain->dt[rk_iova_dte_index(iova)]; + /* Just return 0 if iova is unmapped */ + if (!rk_dte_is_pt_valid(dte)) { + spin_unlock_irqrestore(&rk_domain->dt_lock, flags); + return 0; + } + + pt_phys = rk_dte_pt_address(dte); + pte_addr = (u32 *)phys_to_virt(pt_phys) + rk_iova_pte_index(iova); + unmap_size = rk_iommu_unmap_iova(rk_domain, pte_addr, iova, size); + + spin_unlock_irqrestore(&rk_domain->dt_lock, flags); + + /* Shootdown iotlb entries for iova range that was just unmapped */ + rk_iommu_zap_iova(rk_domain, iova, unmap_size); + + return unmap_size; +} + +static struct rk_iommu *rk_iommu_from_dev(struct device *dev) +{ + struct iommu_group *group; + struct device *iommu_dev; + struct rk_iommu *rk_iommu; + + group = iommu_group_get(dev); + if (!group) + return NULL; + iommu_dev = iommu_group_get_iommudata(group); + rk_iommu = dev_get_drvdata(iommu_dev); + iommu_group_put(group); + + return rk_iommu; +} + +static int rk_iommu_attach_device(struct iommu_domain *domain, + struct device *dev) +{ + struct rk_iommu *iommu; + struct rk_iommu_domain *rk_domain = domain->priv; + unsigned long flags; + int ret; + phys_addr_t dte_addr; + + /* + * Allow 'virtual devices' (e.g., drm) to attach to domain. + * Such a device does not belong to an iommu group. + */ + iommu = rk_iommu_from_dev(dev); + if (!iommu) + return 0; + + ret = rk_iommu_enable_stall(iommu); + if (ret) + return ret; + + ret = rk_iommu_force_reset(iommu); + if (ret) + return ret; + + iommu->domain = domain; + + ret = devm_request_irq(dev, iommu->irq, rk_iommu_irq, + IRQF_SHARED, dev_name(dev), iommu); + if (ret) + return ret; + + dte_addr = virt_to_phys(rk_domain->dt); + rk_iommu_write(iommu, RK_MMU_DTE_ADDR, dte_addr); + rk_iommu_command(iommu, RK_MMU_CMD_ZAP_CACHE); + rk_iommu_write(iommu, RK_MMU_INT_MASK, RK_MMU_IRQ_MASK); + + ret = rk_iommu_enable_paging(iommu); + if (ret) + return ret; + + spin_lock_irqsave(&rk_domain->iommus_lock, flags); + list_add_tail(&iommu->node, &rk_domain->iommus); + spin_unlock_irqrestore(&rk_domain->iommus_lock, flags); + + dev_info(dev, "Attached to iommu domain\n"); + + rk_iommu_disable_stall(iommu); + + return 0; +} + +static void rk_iommu_detach_device(struct iommu_domain *domain, + struct device *dev) +{ + struct rk_iommu *iommu; + struct rk_iommu_domain *rk_domain = domain->priv; + unsigned long flags; + + /* Allow 'virtual devices' (eg drm) to detach from domain */ + iommu = rk_iommu_from_dev(dev); + if (!iommu) + return; + + spin_lock_irqsave(&rk_domain->iommus_lock, flags); + list_del_init(&iommu->node); + spin_unlock_irqrestore(&rk_domain->iommus_lock, flags); + + /* Ignore error while disabling, just keep going */ + rk_iommu_enable_stall(iommu); + rk_iommu_disable_paging(iommu); + rk_iommu_write(iommu, RK_MMU_INT_MASK, 0); + rk_iommu_write(iommu, RK_MMU_DTE_ADDR, 0); + rk_iommu_disable_stall(iommu); + + devm_free_irq(dev, iommu->irq, iommu); + + iommu->domain = NULL; + + dev_info(dev, "Detached from iommu domain\n"); +} + +static int rk_iommu_domain_init(struct iommu_domain *domain) +{ + struct rk_iommu_domain *rk_domain; + + rk_domain = kzalloc(sizeof(*rk_domain), GFP_KERNEL); + if (!rk_domain) + return -ENOMEM; + + /* + * rk32xx iommus use a 2 level pagetable. + * Each level1 (dt) and level2 (pt) table has 1024 4-byte entries. + * Allocate one 4 KiB page for each table. + */ + rk_domain->dt = (u32 *)get_zeroed_page(GFP_KERNEL | GFP_DMA32); + if (!rk_domain->dt) + goto err_dt; + + rk_table_flush(rk_domain->dt, NUM_DT_ENTRIES); + + spin_lock_init(&rk_domain->iommus_lock); + spin_lock_init(&rk_domain->dt_lock); + INIT_LIST_HEAD(&rk_domain->iommus); + + domain->priv = rk_domain; + + return 0; +err_dt: + kfree(rk_domain); + return -ENOMEM; +} + +static void rk_iommu_domain_destroy(struct iommu_domain *domain) +{ + struct rk_iommu_domain *rk_domain = domain->priv; + int i; + + WARN_ON(!list_empty(&rk_domain->iommus)); + + for (i = 0; i < NUM_DT_ENTRIES; i++) { + u32 dte = rk_domain->dt[i]; + if (rk_dte_is_pt_valid(dte)) { + phys_addr_t pt_phys = rk_dte_pt_address(dte); + u32 *page_table = phys_to_virt(pt_phys); + free_page((unsigned long)page_table); + } + } + + free_page((unsigned long)rk_domain->dt); + kfree(domain->priv); + domain->priv = NULL; +} + +static bool rk_iommu_is_dev_iommu_master(struct device *dev) +{ + struct device_node *np = dev->of_node; + int ret; + + /* + * An iommu master has an iommus property containing a list of phandles + * to iommu nodes, each with an #iommu-cells property with value 0. + */ + ret = of_count_phandle_with_args(np, "iommus", "#iommu-cells"); + return (ret > 0); +} + +static int rk_iommu_group_set_iommudata(struct iommu_group *group, + struct device *dev) +{ + struct device_node *np = dev->of_node; + struct platform_device *pd; + int ret; + struct of_phandle_args args; + + /* + * An iommu master has an iommus property containing a list of phandles + * to iommu nodes, each with an #iommu-cells property with value 0. + */ + ret = of_parse_phandle_with_args(np, "iommus", "#iommu-cells", 0, + &args); + if (ret) { + dev_err(dev, "of_parse_phandle_with_args(%s) => %d\n", + np->full_name, ret); + return ret; + } + if (args.args_count != 0) { + dev_err(dev, "incorrect number of iommu params found for %s (found %d, expected 0)\n", + args.np->full_name, args.args_count); + return -EINVAL; + } + + pd = of_find_device_by_node(args.np); + of_node_put(args.np); + if (!pd) { + dev_err(dev, "iommu %s not found\n", args.np->full_name); + return -EPROBE_DEFER; + } + + /* TODO(djkurtz): handle multiple slave iommus for a single master */ + iommu_group_set_iommudata(group, &pd->dev, NULL); + + return 0; +} + +static int rk_iommu_add_device(struct device *dev) +{ + struct iommu_group *group; + int ret; + + if (!rk_iommu_is_dev_iommu_master(dev)) + return -ENODEV; + + group = iommu_group_get(dev); + if (!group) { + group = iommu_group_alloc(); + if (IS_ERR(group)) { + dev_err(dev, "Failed to allocate IOMMU group\n"); + return PTR_ERR(group); + } + } + + ret = iommu_group_add_device(group, dev); + if (ret) + goto err_put_group; + + ret = rk_iommu_group_set_iommudata(group, dev); + if (ret) + goto err_remove_device; + + iommu_group_put(group); + + return 0; + +err_remove_device: + iommu_group_remove_device(dev); +err_put_group: + iommu_group_put(group); + return ret; +} + +static void rk_iommu_remove_device(struct device *dev) +{ + if (!rk_iommu_is_dev_iommu_master(dev)) + return; + + iommu_group_remove_device(dev); +} + +static const struct iommu_ops rk_iommu_ops = { + .domain_init = rk_iommu_domain_init, + .domain_destroy = rk_iommu_domain_destroy, + .attach_dev = rk_iommu_attach_device, + .detach_dev = rk_iommu_detach_device, + .map = rk_iommu_map, + .unmap = rk_iommu_unmap, + .add_device = rk_iommu_add_device, + .remove_device = rk_iommu_remove_device, + .iova_to_phys = rk_iommu_iova_to_phys, + .pgsize_bitmap = RK_IOMMU_PGSIZE_BITMAP, +}; + +static int rk_iommu_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct rk_iommu *iommu; + struct resource *res; + + iommu = devm_kzalloc(dev, sizeof(*iommu), GFP_KERNEL); + if (!iommu) + return -ENOMEM; + + platform_set_drvdata(pdev, iommu); + iommu->dev = dev; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + iommu->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(iommu->base)) + return PTR_ERR(iommu->base); + + iommu->irq = platform_get_irq(pdev, 0); + if (iommu->irq < 0) { + dev_err(dev, "Failed to get IRQ, %d\n", iommu->irq); + return -ENXIO; + } + + return 0; +} + +static int rk_iommu_remove(struct platform_device *pdev) +{ + return 0; +} + +#ifdef CONFIG_OF +static const struct of_device_id rk_iommu_dt_ids[] = { + { .compatible = "rockchip,iommu" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rk_iommu_dt_ids); +#endif + +static struct platform_driver rk_iommu_driver = { + .probe = rk_iommu_probe, + .remove = rk_iommu_remove, + .driver = { + .name = "rk_iommu", + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(rk_iommu_dt_ids), + }, +}; + +static int __init rk_iommu_init(void) +{ + int ret; + + ret = bus_set_iommu(&platform_bus_type, &rk_iommu_ops); + if (ret) + return ret; + + return platform_driver_register(&rk_iommu_driver); +} +static void __exit rk_iommu_exit(void) +{ + platform_driver_unregister(&rk_iommu_driver); +} + +subsys_initcall(rk_iommu_init); +module_exit(rk_iommu_exit); + +MODULE_DESCRIPTION("IOMMU API for Rockchip"); +MODULE_AUTHOR("Simon Xue <xxm@rock-chips.com> and Daniel Kurtz <djkurtz@chromium.org>"); +MODULE_ALIAS("platform:rockchip-iommu"); +MODULE_LICENSE("GPL v2"); |